At present, indoor air in houses, hospitals, buildings, and the like, has been increasingly polluted. Pollutants include dust, molds, ticks, pollens, and various pathogenic germs including influenza viruses, tuberculosis bacteria, methicillin-resistant Staphylococcus aureus (MRSA) as nosocomial infectious bacteria, Legionella bacteria, coronaviruses such as severe acute respiratory syndrome (SARS) viruses, noroviruses, campylobacter, O-157 as food-poisoning germs, and the like. These various kinds of pollutants including floating fungus and airborne infectious germs are suspended in indoor space or attached to indoor wall surfaces, ceilings, furniture, and the like, to thereby deteriorate indoor environments and exert enormous harmful effects on human bodies.
There is suggested an air cleaning device for purifying indoor air polluted by the foregoing pollutants (hereinafter, referred to as “polluted air”) that includes: a wind tunnel with an air inlet and an air outlet vertically arranged; a fan which takes polluted air into the wind tunnel from the air inlet and discharges the same from the air outlet; a nozzle which scatters liquid pressurized by a pump to an entire air path of the wind tunnel; and a collection tank for collecting the liquid, in which the polluted air taken by the fan into the wind tunnel contacts the liquid scattered from the nozzle, whereby the polluted air is purified (for example, refer to Patent Document 1).
In addition, there is suggested another air cleaning device in which pumped-up water is reflected on a mushroom-shaped reflector and turned into a spray of water, and polluted air taken in by an intake fan from an upper entry of a housing contacts the spray of water spreading over the housing, whereby the polluted air is purified (for example, refer to Patent Document 2).
Further, there is suggested another air cleaning device that includes: a housing retaining cleaning water; an air blower which is arranged above the cleaning water to blow polluted air downward from a fan; and a guide which extends from an lower end of the air blower into the cleaning water, increases in diameter downward, has a rib as a spiral projection therein, and is fixed to a rotation shaft of the air blower so as to rotate together with the fan, in which the polluted air blown downward by the fan contacts the cleaning water transferred upward by the rotation of the guide, whereby the polluted air is purified (for example, refer to Patent Document 3).